(a) Field of the Invention
The present invention relates to water flow rate regulating devices, and more particularly relates to a hot/cold water flow rate regulating device which comprises a holder and a cap respectively secured to a mounting plate by a connecting rod and a bolt head stake, which cap comprises a tubular driving member having a spiral track on its inside and rotated by the cap through 300.degree. angle to further force a link to push two valve rod assemblies to move downward or permitting the two valve rod assemblies to be pushed upward by compression springs so as to respectively regulate the flow rate of hot and cold water and cold water into a mixing chamber for further discharge through a water outlet pipe.
(b) Description of the Prior Art
Regular hot/cold water flow rate regulating device generally comprises two separate control knobs respectively for controlling the flow rate of hot water and the flow rate of cold water. This structure is inconvenient in use. There is another type of water tap for regulating hot/cold water flow rate through the control of a hand-hold. In this structure, hot water and cold water are guided into the water chamber, and the water tap through a common water intake hole, and the temperature of mixed water is very difficult to control. When the pressure of cold water surpasses the pressure of hot water, abrupt changes of water temperature will happen. During operation, hot water pipe may be forced by the water pressure from cold water pipe to increase the pressure of the vapor therein, and the vapor will force cold water to flow backward. Therefore, cold water flow rate will be reduced. Once the pressure of the vapor inside hot water pipe is eliminated, cold water flow rate is relatively increased and water temperature of mixed water may become excessively low. In U.S. Pat. No. 2,653,628 there is disclosed a ball valve type of hot/cold water flow regulating device. This structure is still not satisfactory in use. It is easy to damage and can not eliminate water leakage problem. Because of its limited water mixing chamber, water temperature control is more difficult to achieve.